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Date: Fri, 12 Jun 2015 02:50:08 +0200
From: Hans Petter Selasky <hps@selasky.org>
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To: Erich Dollansky <erichsfreebsdlist@alogt.com>, 
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CC: freebsd-hackers@freebsd.org, freebsd-hackers@FreeBSD.org
Subject: Re: allow ffs & co. a binary search
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On 06/12/15 02:10, Erich Dollansky wrote:
> Hi,
>
> On Thu, 11 Jun 2015 08:51:50 -0600
> Ian Lepore <ian@freebsd.org> wrote:
>
>> On Thu, 2015-06-11 at 22:43 +0800, Erich Dollansky wrote:
>>> Hi,
>>>
>>> On Thu, 11 Jun 2015 06:57:51 -0600
>>> Ian Lepore <ian@freebsd.org> wrote:
>>>
>>>> On Thu, 2015-06-11 at 15:21 +0800, Erich Dollansky wrote:
>>>>> On Sun, 07 Jun 2015 08:53:18 +0200
>>>>> Hans Petter Selasky <hps@selasky.org> wrote:
>>>>>
>>>> Is there any reason that this whole change, userland and kernel,
>>>> isn't just:
>>>>
>>>> #define ffs(n) __builtin_ffs(n)
>>>
>>> I did not see this. Where is it?
>>>
>>> Of course, if this is already done, it does not have to be done
>>> again.
>>>
>>> Erich
>>
>> I'm not quite sure what you're asking.  Both clang and gcc support
>> __builtin_ffs(), so I'm saying why don't we just use it and call the
>> whole problem solved?
>>
> so, it is not in the sources yet. Yes, then use it and let the compiler
> guys crack their heads.
>
> Erich

Hi,

Are we depending on that ffs() is a valid symbol when linking?

--HPS